Display screen with a messaging split screen graphical user interface



FIG. 1 is a front view of a display screen with a messaging split screen graphical user interface showing a first embodiment thereof; and,

FIG. 2 is a front view of a display screen with a messaging split screen graphical user interface showing a second embodiment thereof. 

CLAIM I claim the ornamental design for a display screen with a messaging split screen graphical user interface, as shown and described. 